"Chat" Program Problems

Well, ive been trying to make a "Chat" program based on some C# code i found a few days ago, however, ive been pretty unsuccessful. I've pasted the code at a site so that you can copy and past the code to compile it yourself. One of the things that i can't fix is that i can only "send" one message, and i realize that it only displays the first word of the message, but i can't find a way to do that right now. Im not even sure if the Server can send messages right now, but as long as the client can, i can just transfer the code. Another major problem is that if i close the application, either the server or the client, it continues running and i need to use ctrl + alt + del to shut it down. Any help is greatly appreciated. The code is located here:
The Client:http://www.absoluteshells.com/~smoose/client.html
The Server:http://www.absoluteshells.com/~smoose/server.html